QuTiP: Quantum Toolbox in Python

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Welcome to the QuTiP users Group. To join, just post a message!

Note this group is for help in installing or using the toolkit, or general idea for the project.

For issues and ideas about, and contributions to, the QuTiP code go to the QuTiP GitHub

If you need help using QuTiP please look through the old posts before submitting a new one.

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Sturgy Sturges

Jan 30

Elegant way to generate Hamiltonians

Dear all, I'm looking for an elegant way to generate Hamiltonians for interacting two-level

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Elegant way to generate Hamiltonians

Dear all, I'm looking for an elegant way to generate Hamiltonians for interacting two-level

Jan 30

Brett Green, Boxi Li5

Jan 27

Qubit is not affected by simple pulses

Thank you very much! This is great. On Fri, Jan 27, 2023, 10:12 AM Boxi Li <etami...@gmail.com

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Qubit is not affected by simple pulses

Thank you very much! This is great. On Fri, Jan 27, 2023, 10:12 AM Boxi Li <etami...@gmail.com

Jan 27

johny maartin, Gerardo Suarez2

Jan 23

GRAPE on open quantum system

I don't know if qutip GRAPE does, but krotov has its own library based on qutip and can be

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GRAPE on open quantum system

I don't know if qutip GRAPE does, but krotov has its own library based on qutip and can be

Jan 23

Alonsode Jesus Vertel Nieto, Simon Cross3

Jan 6

Dipolar interaction

Hi Simon, thanks for your help. I send you the code in Phyton format, i dont know where is the

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Dipolar interaction

Hi Simon, thanks for your help. I send you the code in Phyton format, i dont know where is the

Jan 6

inspiration lo

Jan 6

problem in run QuTip

Dear QuTiP Team, I have a problem on command: qutip.testing.run() the report comes with: 22 failed,

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problem in run QuTip

Dear QuTiP Team, I have a problem on command: qutip.testing.run() the report comes with: 22 failed,

Jan 6

Yash Tiwari, Simon Cross2

12/27/22

Decay in the expectation value even for unitary evolution in the system?

Hi Yash, Just duplicated my reply from the GitHub issue. The problem with your simulation is that

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Decay in the expectation value even for unitary evolution in the system?

Hi Yash, Just duplicated my reply from the GitHub issue. The problem with your simulation is that

12/27/22

ANUSHREE DEY, Simon Cross4

12/27/22

updated version not found

Hi Anushree, Sorry you haven't managed to fix the issue yet. I'm not sure what to advise next

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updated version not found

Hi Anushree, Sorry you haven't managed to fix the issue yet. I'm not sure what to advise next

12/27/22

Muthumanimaran Vetrivelan, … Simon Cross8

12/21/22

qutip taking more number of cpus in cluster

Glad you came right!

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qutip taking more number of cpus in cluster

Glad you came right!

12/21/22

後藤達也, … ahmed ghareeb15

12/17/22

Bath terminator for time dependent Hamiltonian

I have an idea up till now didn't test it Even you don't have anlytical formula for

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Bath terminator for time dependent Hamiltonian

I have an idea up till now didn't test it Even you don't have anlytical formula for

12/17/22

Simon Cross

12/15/22

QuTiP master transitioning to v5

Greetings, For the last few years we've been developing QuTiP 5 in the dev.major branch. We'

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QuTiP master transitioning to v5

Greetings, For the last few years we've been developing QuTiP 5 in the dev.major branch. We'

12/15/22

Hossein Davoodi Yeganeh, Simon Cross2

12/15/22

mesolve error

Hi Hossein, You can extract the probability for being in particular state psi, but looking at the

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mesolve error

Hi Hossein, You can extract the probability for being in particular state psi, but looking at the

12/15/22

Simon Cross, Boxi Li3

12/13/22

QuTiP 4.7.1

The conda-forge packages are built. > Thank you Simon for the hard work on preparing the release!

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QuTiP 4.7.1

The conda-forge packages are built. > Thank you Simon for the hard work on preparing the release!

12/13/22

Arianna Meinking, Boxi Li2

12/9/22

DispersiveCavityQED Processor to Model Tavis-Cummings Hamiltonian

Hello Arianna, First thing first, I would suggest being consistent, either using only `qutip.qip` or

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DispersiveCavityQED Processor to Model Tavis-Cummings Hamiltonian

Hello Arianna, First thing first, I would suggest being consistent, either using only `qutip.qip` or

12/9/22

Simon Cross

12/8/22

QuTiP 4.7.0 failing to build with latest packaging package

Greetings, This morning's release of the packaging package [1] broke QuTiP's setup.py file [2

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QuTiP 4.7.0 failing to build with latest packaging package

Greetings, This morning's release of the packaging package [1] broke QuTiP's setup.py file [2

12/8/22

John Tu, Neill Lambert2

12/5/22

when ploting a coherent state alpha=1, why the wigner function's result is not in x=1 position?

hi john, The wigner function in qutip uses a particular definition of x and p in wigner(), such that

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when ploting a coherent state alpha=1, why the wigner function's result is not in x=1 position?

hi john, The wigner function in qutip uses a particular definition of x and p in wigner(), such that

12/5/22

Alexander Zotov, Simon Cross2

12/4/22

different results for the same simulations

Hi Alexander, The two notebooks you refer to are from forks of the qutip-notebooks repository, and

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different results for the same simulations

Hi Alexander, The two notebooks you refer to are from forks of the qutip-notebooks repository, and

12/4/22

Simon Cross

12/4/22

Re: SI to simulation units

Hi Alexander, Hopefully my previous answer about QuTiP's units helped -- ie hbar = 1. If hbar is

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Re: SI to simulation units

Hi Alexander, Hopefully my previous answer about QuTiP's units helped -- ie hbar = 1. If hbar is

12/4/22

Simon Cross

12/4/22

Re: units

Hi Alexander, In regards to the units used: In QuTiP Hamiltonians are viewed as already having been

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Re: units

Hi Alexander, In regards to the units used: In QuTiP Hamiltonians are viewed as already having been

12/4/22

Pascal Obled, Simon Cross2

12/4/22

Time dependant collapse operator in mesolve

Hi Pascal, This is indeed somewhat difficult to achieve in QuTiP 4. In the upcoming QuTiP 5, QobjEvo

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Time dependant collapse operator in mesolve

Hi Pascal, This is indeed somewhat difficult to achieve in QuTiP 4. In the upcoming QuTiP 5, QobjEvo

12/4/22

nan wang

11/25/22

How to simulate the EIT-AT effect of four energy level with Qutip

Dear all, Recently, I have encountered the following problems when simulating the Electromagnetically

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How to simulate the EIT-AT effect of four energy level with Qutip

Dear all, Recently, I have encountered the following problems when simulating the Electromagnetically

11/25/22

Simon Cross, Shahnawaz Ahmed2

11/24/22

QuTiP v5 benchmarking live!

Awesome Simon, great work. On Thu, Nov 24, 2022 at 5:25 PM Simon Cross <hodg...@gmail.com>

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QuTiP v5 benchmarking live!

Awesome Simon, great work. On Thu, Nov 24, 2022 at 5:25 PM Simon Cross <hodg...@gmail.com>

11/24/22

Simon Cross, Dawes, Andrew2

11/21/22

Revamped QuTiP tutorials available!

This is excellent work, thank you to everyone involved! These tutorials are a major source of support

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Revamped QuTiP tutorials available!

This is excellent work, thank you to everyone involved! These tutorials are a major source of support

11/21/22

Joan Agusti, Nathan Shammah2

11/9/22

Negativity error fixed

Dear Joan, Thanks for sharing! Would you be keen in opening a pull request on the QuTiP GitHub

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Negativity error fixed

Dear Joan, Thanks for sharing! Would you be keen in opening a pull request on the QuTiP GitHub

11/9/22

Analabha Roy, Simon Cross3

11/9/22

Error in matrix exponentiation?

On Wed, 9 Nov 2022 at 00:32, Simon Cross <hodg...@gmail.com> wrote: Hi Analabha, The

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Error in matrix exponentiation?

On Wed, 9 Nov 2022 at 00:32, Simon Cross <hodg...@gmail.com> wrote: Hi Analabha, The

11/9/22

Soumyabrata Paul2

11/8/22

Erroneous result with position squared expectation value with Fock states

Dear All, The error is in the construction of <x^{2}>. It was my mistake. Please ignore the

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Erroneous result with position squared expectation value with Fock states

Dear All, The error is in the construction of <x^{2}>. It was my mistake. Please ignore the

11/8/22

Thierry Jolicoeur, Simon Cross6

11/5/22

fresh install of QuTIP -> does not pass test

Yay! Happy to help. :D

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fresh install of QuTIP -> does not pass test

Yay! Happy to help. :D

11/5/22

ashish arya, Simon Cross2

11/5/22

Qutrit density matrix

Hi Ashish, QuTiP has a variety of functions for generating random density matrices. For a use case

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Qutrit density matrix

Hi Ashish, QuTiP has a variety of functions for generating random density matrices. For a use case

11/5/22

ph.al...@gmail.com, Simon Cross2

11/5/22

mesolve giving different results for same problem

Yes, I would broadly expect these to give the results. To give more concrete debugging suggestions

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mesolve giving different results for same problem

Yes, I would broadly expect these to give the results. To give more concrete debugging suggestions

11/5/22

Yash Tiwari, Simon Cross2

11/5/22

Numba and GPU (NVDIA CUDA cores) computation with qutip

Hi Yash, You can run your calls to mesolve in parallel using https://qutip.org/docs/latest/apidoc/

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Numba and GPU (NVDIA CUDA cores) computation with qutip

Hi Yash, You can run your calls to mesolve in parallel using https://qutip.org/docs/latest/apidoc/

11/5/22

ashish arya, Neill Lambert3

11/2/22

Wigner function for qutrit system

Thanks Neill for the clarification on specifics of the wigner module of qutip. Ashish Arya On Tue, 1

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Wigner function for qutrit system

Thanks Neill for the clarification on specifics of the wigner module of qutip. Ashish Arya On Tue, 1

11/2/22